ch 2 biology review

atomic number

# of protons in nucleus

Which of these relationships is true of an uncharged atom? a) The number of electrons is equal to the number of neutrons. b) The atomic mass is equal to the atomic number. c) The number of protons is equal to the number of electrons. d) The atomic mass is equal to the number of electrons. e) The number of neutrons is equal to the number of protons.

...

The innermost electron shell of an atom can hold up to _____ electrons.

2

What is the mass number of an ion with 105 electrons, 159 neutrons, and a +1 charge?

265

Which of the following statements about electrons is false? a) The electron is electrically neutral. b) The electron is found outside the nucleus of an atom. c) The symbol for an electron is e. d) The electron has a -1 electrical charge.

A

Which of the following is equal to the mass number? a)protons−neutrons b) protons+neutrons c) protons×neutrons d) protons÷neutrons e) protons+electrons

B

Which of the three subatomic particles has the smallest mass? A)proton B) electron C) neutron

B

Which of the following statements about neutrons is false? a)A neutron has no electrical charge. b)The symbol of a neutron is n. c)The neutron is found in the nucleus of an atom. d)The neutron is positively charged.

D

Which of the following statements about protons is false? a)The proton is positively charged. b) The mass of a proton is about 1 amu. c) The symbol for a proton is p. d) The proton is found outside the nucleus of an atom.

D

which subatomic particle has a mass of 1/2000 amu?

electron

A substance that cannot be broken down into other substances by ordinary chemical procedures is a(n) _____.

element

Which subatomic particle has a mass of 1 amu?

proton neutron

The ________, ______, and _______are the three main subatomic particles that make up all the elements.

proton, neutron, and electron

mass number

protons + neutrons

if # of (-) electrons is equal to the # of (+) protons then________

the atom is neutral

if # of protons and electrons are not equal then.....

the atom will have a charge